Project Summary/Abstract: Neurocognitive disorders (e.g., Alzheimer?s disease) are major public health problems that may disproportionately affect Latinos compared to other Americans. Extant dementia literature from outstanding neuroepidemiologic work indicates that some Latino ancestry groups may have a four-fold increased risk of dementing disorders (e.g., Alzheimer?s disease) compared to other Latino groups. The reasons for these striking differences in dementia estimates have not been addressed; represent a major gap in the health scientific literature; and form a major barrier to progress in better understanding dementias among diverse Latino populations. Furthermore, less is known about midlife factors associated with early and pathological neurocognitive deficits and disorders, regardless of ethnicity/race. Insights from middle-aged and older Latino populations will open new opportunities for mitigating further neurocognitive disorder and related disabilities. Logistically and economically, sampling sufficient numbers of major Latino groups (e.g., Mexicans, Puerto Ricans, Cubans, Dominicans) for well-powered neuroepidemiologic work is prohibitive and forms additional barriers to progress in the field. As an invited Ancillary Study of the Hispanic Community Health Study/Study of Latinos (SOL; n=16,415 at baseline), this proposed project designated as the Study of Latinos-Investigation of Neurocognitive Aging (SOL-INCA) would efficiently fill major gaps in the neuroepidemiology Mild Cognitive Impairment/Mild Neurocognitive Disorders (MCI/mNCD). SOL-INCA would examine associations between shared genetic and cardiovascular disease risk factors for neurocognitive deficits and disorders (i.e., MCI/mNCD) among SOL?s middle-aged and older Latino subsample (n=9,652 at baseline). Additionally, SOL-INCA would begin to unveil the sociocultural risks and protective factors that may contribute the striking differences in dementia previously found between Latino ancestry groups. SOL-INCA would be integrated into Visit 2 to collect a second time-point of neurocognitive data from returning SOL middle-aged and older Latinos participants (ages 50-80 years old; 2015-2020). We believe that the SOL-INCA approach would enable us to discover behaviorally, culturally appropriate, and biologically plausible targets and means for mitigating early neurocognitive disorders. Our long-term is to translate our findings into actionable means for preventing or delaying milder forms of neurocognitive disorders from evolving into more severe disordered states, especially in Latinos who may be at increased risk for these disorders.